wet & dry batteries

1. Batteries
Battery is a storage device used for the storage of chemical energy and
for transformation of Chemical Energy in to Electrical Energy.

2. Anatomy of a Battery
 The internal workings of a battery are typically housed within a metal or
plastic case. Inside this case are a cathode, which connects to the positive
terminal, and an anode, which connects to the negative terminal. These
components, more generally known as electrodes.
 A separator creates a barrier between the cathode and anode, preventing the
electrodes from touching while allowing electrical charge to flow freely
between them….
 Batteries are used in many applications, Automobile Industry, Power sector &
in other Industrial Applications.
 In Automobiles energy from the battery is used to power accessories, lighting
and other electrical systems when the engine is not running. To supply the
ignition, fuel and starting systems with the necessary power to start the
vehicle

3. Anatomy of a Battery
 The medium that allows the electric charge to flow between the cathode and
anode is known as the electrolyte

4. What does a battery do?
 Static discharge is the moving of electrons from one atom to another.
 In order to keep the electrons moving through the circuit, there has to be
something that causes a push, or a voltage difference- a battery does just
that…

5. How do batteries work?
 Batteries create an uneven level of electrons which causes the electrons to
move from a high concentration to a low concentration…
 This is also known as the voltage difference.
 The reaction in the anode creates electrons, and the reaction in the cathode
absorbs them. The net product is electricity.

6. What are the different types of batteries?
Two Major Type of Batteries.
Wet-Cell & Dry-Cell Batteries.
Modern batteries use a variety of chemicals to power their reactions. Some of
the more common types of batteries are:
 Zinc-carbon battery or standard carbon battery
 Alkaline battery
 Lithium battery
 Lithium-ion battery
 Lead-acid battery
 Nickel-cadmium or NiCad battery

7. Wet cell – Dry cell Batteries
 Wet cell batteries contain a liquid electrolyte solution which consists of
sulphuric acid and water. Also known as Vented/flooded acid batteries
 Wet cells will produce 2.1 Volts each and 6 cells connected in series (+ - )
allows them to produce the 12.6 - (12) Volts used by the automobile.
 The main concern for wet cell batteries in all applications is leaking sulfuric
acid, as it is a dangerous corrosive that can damage what it contacts and can
burn human tissue.
 Dry cell batteries will only produce 1.5 Volts per cell and can be connected in
series (to produce more voltage). Dry cell batteries are batteries, which the
electrolytes are in form of moist paste. They also refer to electrical batteries,
which the electrochemical cells converts stored chemical energy into
electrical energy.

8. Wet cell Batteries
5. Lead-acid battery:
 This is the chemistry used in a typical car battery. The electrodes are usually
made of lead dioxide and metallic lead, while the electrolyte is a sulfuric acid
solution. The amount and size of plates in a battery cell, determine the
capacity of the battery.
 Example,
 Automobiles Batteries.

9. Dry cell Batteries
1. Zinc-carbon battery:
 Zinc and carbon are used in all regular or standard AA, C and D dry-cell
batteries. The electrodes are made of zinc and carbon, with a paste of acidic
materials (ammonium chloride or zinc chloride) between them serving as the
electrolyte.
2. Alkaline battery:
 This chemistry is common in AA, C and D dry cell batteries. The cathode is
composed of a manganese dioxide mixture, while the anode is a zinc powder.
It gets its name from the potassium hydroxide electrolyte, which is an
alkaline substance……

10. Dry cell Batteries
3. Lithium battery:
 These batteries are used in cameras for the flash bulb. They are made with
lithium, lithium-iodide and lead-iodide. They can supply surges of electricity
for the flash.
4. Lithium-ion battery:
 Lithium chemistry is often used in high-performance devices, such as cell
phones, digital cameras and even electric cars. A variety of substances are
used in lithium batteries, but a common combination is a lithium cobalt oxide
cathode and a carbon anode.
5. Nickel-Cadmium(nicad) Batteries:
 The nicad system requires 10 series cells to reach a potential of 12 VDC.

11. Dry Cell Battery

12. Selection and Sizing of Battery
 The duty cycle imposed on the battery will depend on the DC system design
and the load requirements. The duty cycle showing the battery loads in
amperes and the lengths of time for which they must be supported will
determine the sizing of the battery. Loads may be classified as continuous or
non-continuous.

13. Selection and Sizing of Battery
Continuous loads:
Continuous loads are classified as steady-state loads. Continuous loads are
energized throughout the duty cycle and are normally supplied by the battery
charger. Examples of typical continuous loads are
• Lighting
• Indicating lights
• Continuously energized coils and operating motors

14. Selection and Sizing of Battery
Non-continuous loads
Non-continuous loads lasting 1 min or less are known as momentary loads or
short-time loads. Examples of typical non-continuous loads are
• Circuit breaker operations
• Motor operated valves
• Inrush currents of motors or other devices
• Field flashing of generators or synchronous motors

15. Maintenance and Care of Batteries for
Long Life
The monitoring and maintenance of batteries is very important from the point of view
of service reliability.
 Inspections:
Periodic inspection can provide information on the battery conditions and its state of
health. All inspections should be made under normal float conditions. Inspection
should be made at least once a month and should include the following checks:
 Float voltage at battery terminals
 Charger output current and voltage
 General appearance and cleanliness of the battery
 Electrolyte levels, cracks in jars, and leakage of electrolyte
 Evidence of corrosion at terminals, connectors, racks, or cabinets

16. Wet & Dry Cell Merits & Demerits
 Merits:
1. Most economical among diff types of
batteries.
2. Robust- not much sensitive to
temperature.
 Demerits
1. Needs periodic maintenance- twice a
month.
2. Emits corrosive fumes.
3. Needs special battery room with acid
proof tilling.
4. Cannot be transported in charged
condition, initial charging takes 55 to
90 hours.
5. Needs specially trained persons for
handling due highly hazardous
sulphuric acid.
 Merits:
 These Cells have voltage ranging
from 1.25V-1.50V
 Small sized, Primary Cells are used in
torches, radios, hearing aid devices,
watches etc.
 Demerits
 These cells does not have long life,
because the Acidic NH4Cl corrodes
the container even when the cells
are not in use.